vormals fr



philosophy, (assignors to the FARBENFABRIQ UNITED STATES PATENT OFFICE.

MORITZ ULRICH AND J OHANN r BAMMANN OE ELBERFELD GERMANY,

ASSIGNORS ,TO THE FARBENFABRIKEN, VORMALS FR. BA YER & 00.,

OF SAME PLACE.

BLUE COLORING-MATTER PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 506,284, dated October 10, 1893. Application filed May 9,1893. seen No. 473,578. (No specimens.)

To all whom it may concern: I

Be it known that we, MORITZ ULRICH and J OHANN BAMMANN, chemists and doctors of KEN, VORMALS FR. BAYER & 00., of Elberfeld,) residing at Elberfeld, Prussia, Germany,

. have invented a new and useful Improvement in the Manufacture of Blue Coloring-Matters; and we do hereby declare. the following to be an exact and clear description of our invention.

The resulting coloring-matters have the following general formula, (in which: RR signifies the radical of the tetrazotized tolidin or dianisidinz) Our invention relates to the manufacture of coloring-matter producing on unmordanted.

' from the reaction of one molecular proportion of the tetrazocompound of tolidin or dianisidin with two molecular proportions of 1:8 amidonaphthol-alpha mono sulfo acid (NH :SO H:OH=1: 4:8) in an alkaline solution.

In carrying out our invention practically we can proceed as follows: 5.3 parts, by weight, of tolidin (or the corresponding quantity of dianisidin) are converted in the well known manner with twelve parts, by weight, of hydrochloric acid (25 Baum) and 3.5 parts, by weight, of sodium nitrite into the tetrazocompound. Fifteen parts, by weight, of the sodium salt of amidonaphthol alpha mono sulfo acid (NH SO H: OH=1:4:8) are dissolved in three hundred parts, by weight, of water with the addition of thirty parts, by Weight, of sodium carbonate (Na C0 The aforesaid tetrazo solution is poured into the alkaline solution of the amidonaphthol sulfo acid, carefully cooling by means of ice. The formation of the new dye-stulf begins almost directly and is completed by allowing the reaction mixture to stand for about twentyfour hours at ordinary temperature that is to say at from about l0 to 20 centigrade. Then, the mixture is slowly heatedto about centigrade. rated by means of common salt and is filtered off, pressed anddried.

The new dye-stuff is sepa- The coloring-matter thus obtained forms a Y dark powder with metallic luster, easily soluble in water with a violet-blue color, soluble" in ammonia with a blue color, insoluble in concentrated sodium carbonate and soda-lye. By concentrated sulfuric acid (66 Baum) it is dissolved with a greenish-blue color, first turning into red on adding ice-water to the sulfuric acid solution. The free sulfo acid of the coloring-matter then being separated in 2. As a new manufacture the coloring-matters having the general formula:

(in which formula RR signifies the radical of the tetrazotized tolidin or dianisidin) and which is easily soluble in water with a violet-blue color, insoluble in concentrated sodium carbonate and soda-lye, forming with concentrated sulfuric acid (66 Bamn) from In testimony whereof We have signed our 10 blue to greenish-blue solution, the latter first names in the presence of two subscribing witturning into red on the addition of ice-Water, nesses.

and then a blue flaky precipitate being sepa- 5 rated, producing on unmordanted cotton from blue to greenish-blue shades fast to the action of alkali and acid, and being further di- 'Witnesses: azotizable, when fixed on the fiber, substan- WILLIAM ESSENWEIN,

tially as described. RUDOLPH FRICKE. 

